Each triangle is approximately 5.25” along each side when worked with 5.5mm hook with dk yarn. (4.5” tall)
Pattern link to webarchive

My maths led me to needing 280 (ish) triangles to make a blanket the same size (55”x89”) as the pattern. Though it may need a few more or less to complete the right shape. I don’t think this is right now!

It was Suzapalooza’s blanket that inspired me to crochet this pattern so I’m going to go with a similar ratio of colours.
I got 14 triangles out of 1 ball of the bright purple, so assuming I get the same number from the stylecraft special…
25 balls x14triangles = 350 total
11 triangles wide (x2 to make a row) x 16 rows high (352 triangles)
Size: 58” x 72” (straight top - wavey sides)

Using 5.0mm hook for the kirkhouse bright purple - otherwise they come out a tad big.
5.5mm for all the others and for joining.
Joining with Emperor.

So the colours;
Kirkhouse bright purple - 6 - 18+37 +15 = 75
Special Emperor - 6 18+42 = 60
Special Parma Violet - 2 3+26 + 26 = 55
Special Violet - 3 9+40 = 49
Special Wysteria - 1 3+20 (23) 12??
Special Graphite - 3 (4?) - 12+27 + 11 = 50
Special Grey - 1 3+8 = 11
Special Silver - 2 - 7+23 +14 = 44
Special Midnight - 1 3+10 = 13

Special Viola?? Speckle - don’t like it.

29/12/17 - 75 crocheted together and many more made.
28/06/17 - 75 together + approx 130.
Midnight , Violet , wisteria , Parma Violet , grey , see top photo. More emperor, more bright purple, more graphite, more silver needed

01/03/19 - 219? Done.
23/09/19 - 75 + 170? Done.
12/04/20 - 268? Done
22/04/20 - 281+ 3 done

31/08/20 - 298 done
07/09/20 - 298 in box + 15 bright purple + 12 Parma violet.

20/10/21 - all seams joined with single crochet, 2 rounds of single crochet around the edge.
Done!